Can drinking tea reduce stroke risk? Why are there rumors that it causes cancer? An article to give you popular science!

The culture of growing and drinking tea in China has a long history, and relevant research shows that China is the starting point of the world's tea culture. Even now, there are many young people who like to drink a cup of tea in their spare time.

　　They found that the aromatic smell in tea has the magical effect of refreshing and increasing vitality. Moreover, health experts have also said that drinking tea does have certain health benefits.

　　Not only that, but related research points out that drinking tea can also reduce the risk of stroke!

Stroke must be familiar to everyone. It is one of the cardiovascular　　and cerebrovascular diseases with high incidence in middle-aged and elderly people .

　　Judging from the current clinical data, the causes of stroke are quite complex, including genetics, aging and vascular aging, three high diseases, unhealthy living and eating habits , etc.

　　The Chinese research team has conducted relevant investigations and studies on tea. Since the mid-2000s, the research team has focused on people aged 50 to 74 , with 365,682 volunteers . At the same time, the research team also focused on people who had not had a stroke before, tracking them for about 11.4 years in total .

　　Among these volunteers, 10,053 stroke patients occurred . The results of the study show that people who drink 3-5 or 4-6 cups of tea a day have a relatively lower risk of stroke, which can be reduced by about 32% . The reason for this is that tea contains many beneficial components, including tea pigments, theophylline and tea polyamines , etc. These beneficial components have the effect of maintaining blood vessels.

　　Of course, this study does not point to an absolute equivalence between stroke and tea. As mentioned above, there are many high-risk factors for stroke, and this experiment did not exclude many high-risk factors, and the age of the survey is the high-risk age for stroke . Therefore, this experiment can only show that tea has the effect of health preservation, but it does not mean that it can directly prevent stroke.

　　So the question is, since tea has the effect of health preservation, why are there rumors that it can cause cancer?

　　In 2019, the Chinese research team also conducted a follow-up survey on more than 500,000 Chinese people who drink tea. The results show that compared with people who drink tea less than once a week, people who drink more than 4g of tea a day have a significant risk of cancer. The increase in cancer can reach about 26% , especially the incidence of gastric cancer and lung cancer , which has increased to about 29% and 62% .

　　However, the research team also clearly pointed out that the reason for such a conclusion does not directly explain the relationship between tea and cancer. Because some people in this group also have other bad habits, such as smoking and drinking .

　　Moreover, they often think that drinking tea can offset the harm caused by tobacco and alcohol, so they are prone to unbridled smoking addiction. After adjusting the amount of smoking, the association between drinking tea and cancer became weaker, so there is no clear conclusion so far that drinking tea causes cancer.

　　However, there may be a close relationship between drinking tea and esophageal cancer and stomach cancer. However, it is not the tea or the tea itself, but the temperature of the tea. Many Chinese people are accustomed to drinking hot tea, believing that only hot tea can stimulate the aroma of tea leaves.

　　And this will just cause damage to the mucosa of the digestive tract, which in turn increases the chance of canceration. The WHO has already discovered this, and has listed food or water above 65°C as a Category 2a carcinogen.